First Lady Michelle Obama is back on the campaign trail for the first time in two years, as Democrats seek to gain momentum ahead of the November elections.

Democrats call Mrs. Obama their secret weapon, and President Barack Obama has dubbed her "The Closer."

While talking to radio show host Tom Joyner Thursday, she thanked supporters for their prayers and encouragement.

"We're all proud of Barack and his accomplishments. Everybody I know in our communities are praying for us. Every day we feel that," she said. "And let me just tell your listeners that it means all the world to us to know that there are prayer circles out there and people who are keeping the spirits clean around us."

The first lady will stop in eight key states to drum up Democratic support. She went home to Chicago Wednesday to raise money for U.S. Senate candidate Alexi Giannoulias and Democrats running for Congress. On Thursday, she cast an early ballot and encouraged others to do the same.

Mrs. Obama has an approval rating of 65 percent - significantly higher than her husband's. Her appearances have raised as much as $400,000.